LOVE BITES.('Private Lives')(Theater Review)

On Noel Coward's bookplates was a caricature of him winking--a gesture that announced both his raffish insouciance and his high-camp refusal to suffer. Coward was his own unrepentant invention, and he made a myth of his separation from others. "I am related to no one except myself," he said. He was an egotist; he was a gay man who passed for a heterosexual matinee idol; and he had the public's number. His wink was the visual equivalent of a raspberry blown at convention. Coward gives that impulse a voice in the most gossamer of his good plays, "Private Lives," when his spokesman Elyot Chase says, "Let's be superficial and pity the poor philosophers. Let's blow trumpets ...